As an experiment, I put a selection of different mystery pieces on a damp towel in a plastic container. It's on a shelf outside with indirect sun and the top loosely on. I'll know which bit is the seed when it sprouts.

I'm a little late responding to this but in case it is still useful...

I have been saving German Chamomile for many years, and feel that it would by kind of nuts to be uptight about the chaff because the seeds are almost microscopic and don't roll out of the chaff. So I just pinch the central "puffs" of the flowers shortly before they will fall apart and set them in a dish out of the breeze to dry, chaff and all. Germination seems to work fine. Usually the chamomile self-sows, but not always where I want.

If I were to trade that seed, I would just mention that chaff is included.